Owing to their low polarity, diorganopolysiloxanes most often exhibit a hydrophobic surface. It is of great importance to increase their hydrophilicity, for example, in silicone-based dental impression compounds in order to improve water wettability, in sealing compounds in order to improve overcoatability with aqueous emulsion paints, and in the surface treatment of fibers or textiles in order to improve the handle. The use of organopolysiloxanes containing polar groups allows the modification of the polarity and thus the surface energy in such a manner that the hydrophilicity of the siloxane is improved. Owing to their commercial availability, their neutrality and the relatively high chemical stability, polyether radicals are often used as the polar groups. See U.S. Pat. No. 3,565,845 (Union Carbide Corp; issued on Feb. 23, 1971) and corresponding DE-B 1,947,268 and U.S. Pat. No. 4,657,959 (Minnesota Mining Mfg Co., issued on Apr. 14, 1987) and corresponding WO-A 87/03001.
In cases wherein crosslinkability of the hydrophilic organopolysiloxane is desirable, in order to increase the durability of the hydrophilic properties the siloxane skeleton must contain further crosslinkable groups. See U.S. Pat. No. 4,283,519 (Union Carbide Corp., issued on Jul. 22, 1981) and the corresponding EP-A 32310 and U.S. Pat. No. 4,552,919 (Toray Silicone Co. Ltd., issued on Nov. 12, 1985). The disadvantage of such compositions is that crosslinking of the hydrolyzable functions upon intake of moisture is only possible at elevated temperature and/or in the presence of metal catalysts.